Occupant restraint systems in vehicles typically include three-point seat belt systems. Three-point seat belt systems often use a webbing slidably anchored to structural parts of the vehicle, e.g., a pillar, a seat frame, and a vehicle floor. Vehicle seat belt systems further typically include a pretensioner and other load limiting mechanisms to control forward motion of an occupant during a crash event. However, the pretensioner adds cost and complexity to the seat belt system.